1. Field of the Invention
This invention pertains to wall construction, and more particularly to apparatus for erecting insulated concrete walls.
2. Description of the Prior Art
It is well known to construct walls using insulated concrete forming systems. For the purposes of the present invention, the term “insulated concrete forming” means a concrete forming system using stay-in-place forms of foam plastic insulation for constructing cast-in-place concrete walls. Insulated concrete forming systems combine the inherent structural integrity of concrete with the energy efficiency of rigid insulation.
Typically, insulated concrete forming systems include a number of blocks, each comprising a pair of parallel panels spaced apart by the thickness of the concrete wall. The panels are held to each other at the proper spacing by ties of metal, plastic, or other material. The blocks are stacked on top of and alongside each other to suit a particular wall. After all the blocks have been are erected in place, concrete is poured in the space between the panels.
Representative companies that manufacture insulated concrete forming systems include R-Forms, Inc. of Naples, Fla.; and Poly-Forms LLC of Taftville, Conn. Other examples of insulated concrete forms may be seen in U.S. Pat. Nos. 4,706,429; 4,730,422; 4,731,968; 4,765,109; 4,866,891; 4,884,382; 5,140,794; 5,428,933; 5,625,989; 5,657,600; 5,735,093; 5,992,114; and 6,363,683. The form of the foregoing patents are rigid in that the panels are always spaced a fixed distance apart.
U.S. Pat. Nos. 4,742,659, 4,888,931, 4,901,494 and 5,890,337 disclose forms that have at least limited capabilities of folding. However, none of the foldable forms is rigidly lockable in the unfolded configuration.
A common characteristic of many prior insulated concrete forming systems was that the panels were rigidly tied together at the factory to make a block. As a result, the envelopes of the blocks were fixed. The space between the panels occupied a large percentage of the total block envelope. The space between the panels, which was vital for eventually receiving poured concrete, nevertheless was highly undesirable for shipping and storage purposes. In some prior designs, the ties were separate from the panels such that the panels could be laid flat against one another for shipping and storage. Once the ties were assembled between two panels, however, the resulting blocks were permanently rigid unless the ties were removed.
Prior insulated concrete forming systems suffered another handicap concerning corners of a wall. To suit both L-corners and T-corners, the prior systems required special blocks. The costs associated with designing, manufacturing, storing, and using multiple kinds of corner blocks was undesirable.
Thus, despite the widespread availability of insulated concrete forming systems, further developments to them are desirable.